Notecard Cell + WiFi: Unexpected Cellular Fallback Despite Strong Wi-Fi Connection

Hi,

I’ve noticed that some of my Cell + WiFi Notecards occasionally connect to cellular, even when a strong configured Wi-Fi network is available. This was particularly surprising in a basement location where cellular signal is very weak (LTE RSSI always below -90 dBm), but the Wi-Fi signal remains strong (-60 to -40 dBm). This situation is the only one where it causes issues.

For the basement scenario, I switched to a Wi-Fi-only Notecard (I realized there is no sense in using Cell + WiFi if there is no cell available anyway), which resolved the issue, but I’d still like to understand why this behavior occurred with the Cell + WiFi Notecard.

I’m curious about what might be triggering the fallback to cellular. From the session logs, the Wi-Fi signal never appeared weak before the switch. Could there be other factors influencing the Notecard’s decision to use cellular?

Any insights would be appreciated! :slight_smile:

Hi @tsuzenski,

One thing I would check is to make sure the 2.4 GHz network on your router isn’t going down (and then restarting). This happened with my home router - and since there were hardly any devices on the 2.4 band, I didn’t notice it on my laptop etc.

Otherwise, if your Wi-Fi access point isn’t found during scanning or there is a connection timeout and it happens 3 consecutive times, it’ll be sensitive to this and switch over to cellular.

You can also test your Notecard Cell+WiFi in Wi-Fi only mode with:

{
  "req": "card.transport",
  "method": "wifi"
}

…and see if you notice any difference. Make sure you’re on the latest firmware too!

2 Likes

Thank you, Rob! This helps. Using Wi-Fi only maintains a successful connection and is what we are going to use for locations with no cellular. I am also going to check with our IT department to see if they can notice any similar router behavior to yours with our IoT network. :slight_smile: